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Effect of caffeine and beetroot juice supplementation on specific judo performance

The effect of caffeine and beetroot juice supplementation on specific judo performance during simulated competition-day conditions in judo athletes

Status
Active, not recruiting
Phases
Phase 3
Study type
Interventional
Source
IRCT
Registry ID
IRCT20231004059615N5
Enrollment
24
Registered
2025-07-18
Start date
2025-07-23
Completion date
Unknown
Last updated
2026-02-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Improve exercise performance.

Interventions

Intervention 1: Intervention group1: Beetroot juice supplement (BEET It Sport®
James White Drinks Ltd., Ipswich, UK)
2 days before the test: 2 servings, 70 ml each, containing approximately 6.4 mmol nitrate
1 day before the test: 2 servings, 70 ml each, containing approximately 6.4 mmol nitrate
Test day: 2 servings, 2 hours before the test and after the second randori, 70 ml, containing approximately 6.4 mmol nitrate. Intervention 2: Intervention group 2: Caffeine supplement (Caffeine®, Olim
Test day: 3 servings, 1 hour before the test and after the second and fourth attempts, 2 mg/kg body weight each. Intervention 3: Intervention group 3: Beetroot juice supplement (BEET It Sport®
2 days before the test: 2 servings, each 70 ml, containing approximately 6.4 mmol nitrate
1 day before the test: 2 servings, each 70 ml, containing approximately 6.4 mmol nitrate
Test day: 2 servings, 2 hours before the test and after the second attempt, 70 ml, containing approximately 6.4 mmol nitrate. Caffeine supplement (Caffeine®, Olimp Laboratories, Poland)
Test day: 3 servings, 1 hour before the test and after the second and fourth attempts, 2 mg/kg body weight each. Intervention 4: Control group: Similar to the intervention condition, they will receive

Sponsors

INTERNATIONAL SCIENCE AND TECHNOLOGY UNIVERSITY
Lead Sponsor

Eligibility

Sex/Gender
All
Age
18 Years to 30 Years

Inclusion criteria

Inclusion criteria: All male judokas between the ages of 18 and 30. Have a training history of more than 5 years. Have at least a brown belt in judo. Do not smoke. Do not drink alcohol. Have a daily caffeine intake of less than 100 mg.

Exclusion criteria

Exclusion criteria: Have any illness or injury in the past 3 months Take any medication or nutritional supplement in the past 3 months

Design outcomes

Primary

MeasureTime frame
SJFT index. Timepoint: In the 6 stages after judo randori. Method of measurement: Using the following formula: SJFT index = HR0 + HR1 / total number of throws.;Cognitive function. Timepoint: At baseline and after SJFT. Method of measurement: Using the Psychomotor Vigilance Test.

Secondary

MeasureTime frame
Number of throws. Timepoint: In the 6 stages after SJFT. Method of measurement: Counting the number.;Heart rate. Timepoint: In the 6 stages immediately at the end of SJFT and 1 minute after SJFT. Method of measurement: Using a Polar heart rate monitor.;Rate of perceived exertion. Timepoint: In the 6 stages after SJFT. Method of measurement: Using the Borg scale.;Jump height. Timepoint: In the 6 stages (pre-exercise and after SJFT). Method of measurement: CMJ Test.;Muscular strength. Timepoint: In the 6 stages (pre-exercise and after SJFT). Method of measurement: Isometric strength testing device for hand muscles.;Blood lactate. Timepoint: At baseline, pre-exercise, mid-exercise, pre-final SJFT and post-exercise. Method of measurement: Via Enzyme-Linked Immunosorbent Assay.;Muscle oxygenation. Timepoint: During the final SJFT. Method of measurement: Near-infrared spectroscopy.;Blood glucose. Timepoint: At baseline, pre-exercise, mid-exercise, pre-final SJFT and post-exercise. Method of measurement: Via hexokinase method.;Plasma nitrate and nitrite. Timepoint: At baseline, pre-exercise, mid-exercise, pre-final SJFT and post-exercise. Method of measurement: Via chemiluminescence assay.;Blood caffeine. Timepoint: At baseline, pre-exercise, mid-exercise, pre-final SJFT and post-exercise. Method of measurement: Via High-Performance Liquid Chromatography.;Blood PH. Timepoint: At baseline and post-exercise. Method of measurement: Blood gas analyzer.

Countries

Turkey

Contacts

Public ContactDavar Khodadadi

Islamic Azad University

davar.khodadadi@yahoo.com+98 21 2263 3583

Outcome results

None listed

Source: IRCT (via WHO ICTRP) · Data processed: Feb 7, 2026